A prospective study to validate the Polish language version of the European Organisation for Research and Treatment of Cancer (EORTC) Colorectal Liver Metastases (QLQ-LMC21) module.

PURPOSE

This validation study was designed to assess the psychometric validity and quality of the Polish translation of the EORTC QLQ-LMC21 questionnaire in Polish colorectal patients suffering with liver metastases.

METHODS

Patients with either histopathological or imaging confirmation of colorectal cancer with liver metastases, with a minimum of three months survival, were eligible for this study. These patients completed the Polish version of the EORTC core QLQ-C30, the QLQ-LMC21 module, and a demographic data questionnaire. The questionnaires were completed twice, once before undergoing either hepatectomy (n = 63) or palliative treatment (n = 97) and three months after the primary treatment. Standardized analyses of validity and reliability were performed.

RESULTS

One hundred and sixty patients were enrolled in this study with the mean age of the hepatectomy group 64.3 ± 14.1 and 66.1 ± 12.7 for the palliative treatment group. The QLQ-LMC21 exhibited positive internal consistency with Cronbach's alpha coefficients ranging from 0.72 to 0.90. The multi-trait scaling analysis demonstrated adequate convergent and discriminant validity. Test-retest reliability was undertaken with 40 patients (25%) with the ICCs for each item ranging from 0.64 to 0.88. The hepatectomy group had a significantly greater Karnofsky Performance Score than the palliative treatment group (p.<0.001). Overall there were weak correlations between the two questionnaires which confirm that the QLQ-LMC21 addresses health issues not assessed in the QLQ-C30.

CONCLUSION

The Polish version of the QLQ-LMC21 proved to be a valid and reliable questionnaire to use in conjunction with the QLQ-C30 core questionnaire.